00010 PROCEDURE MEDIAN; 00020 00030 BEGIN 00040 00050 IF (Y1[I]>Y2[I])∧(Y>Y2[I]) THEN BEGIN 00060 IF Y1[I]>Y THEN Y2[I]←Y ELSE Y2[I]←Y1[I];END; 00070 00080 IF (Y[1]<Y[2])∧(Y<Y2[I]) THEN BEGIN 00090 IF Y1[I]<Y THEN Y2[I]←Y ELSE Y2[I]←Y1[I]; END; 00100 00105 Y1[I]←Y2[I]; Y2[I]←Y; Y←Y1[I]; X1←X2; X2←X; X←X1; 00110 END;